The relationship between atmospheric blocking and temperature anomalies in Turkey between 1977 and 2016

Abstract

The relationship between the character of atmospheric blocking and surface temperature has not been studied in depth for Turkey. Here, these relationships are investigated for the period 1977–2016. The seasonal mean temperature anomalies for all stations during blocked days varies between −2.1 and 0.8°C. There are four main patterns representing the mean seasonal temperature anomalies for all stations during blocked and non‐blocked days. The annual cycle for each group is nearly opposite, and this indicates the impact of blocking on observed temperature, as blocked days comprised 30% of the study period. When focusing on the spatial distribution of mean seasonal anomalies, the winter and fall seasons show that, almost all stations have negative temperature anomalies although anomalies are close to zero during warm seasons (spring and summer). The composite analysis shows that the western part of the country is strongly affected by cold air advection during upstream blocking events and the eastern part of the country is affected by warm temperature advection for downstream blocking events. There is a statistically significant (95% confidence level) negative correlation between blocking intensity and temperature anomalies in all seasons except spring. There is no relationship between both blocking duration and longitudinal extent and the seasonal mean temperature anomaly except during winter, which has a significant negative correlation. The temperature anomaly distribution stratified by season shows that strong positive anomalies are rarely observed in all seasons. Only winter and spring were associated with very strong positive anomalies and only at a few stations. Rex‐type atmospheric blocking events are observed during the period of not only the maximum temperature anomaly but also for minimum anomalies. However, the location of the blocking event differed from the typical situation above, with the cold and warm events being located downstream and upstream of Turkey, respectively.

Atmospheric blocking events: a review

“…However, a wide range of other types of extreme weather events have been attributed to the blocking environment, such as cold waves, 46,47,63,[72][73][74][75] extreme precipitation and flooding, 76,77 summer season thunderstorm activity, 78 blizzards, 79,80 as well as having an impact on the weather for entire seasons. 75,80,81 Within the last two decades, atmospheric blocking has also been shown to affect air masses and air mass transport across the globe in the troposphere, 82 as well as the stratospheric weather (sudden stratospheric warming or variability, e.g., Refs. [83][84][85][86], including photochemistry in this part of the atmosphere.…”

Samsun İli Yağış Ve Sıcaklık Verilerinin Şen Yenilikçi Trend Yöntemi İle Trend Analizi

“…Sıcaklık ve yağış, araştırmacılar tarafından detaylı bir şekilde incelenmiştir. Araştırmacıların bir kısmı, bazı atmosferik olayların yağışa [5], sıcaklığa [6] ve uç sıaklıklara etkisini [7] incelemiş; bir kısmı, yağış sıklığını sınıflamış ve tahmin etmeye çalışmış [8]; bir kısmı da bazı önemli olayları incelemiştir [9]. Tabii ki en çok araştırma sıcaklık ve yağış verilerinin trend analizleri konusunda yapılmıştır.…”

An Investigation of Critical Fire Weather Patterns: A Case Study

“…Dong et al provided a unique case study, focused on the whole of the US during 13-17 August, 2007, in which blocking, drought, heat waves and an urban heat island all occurred concurrently, concluding that atmospheric blocking is capable of reinforcing droughts, initiating heat waves, and probably amplifying the urban heat island intensity during [10]. Woollings et al reviewed the research on blocking under climate change, with the aim of providing an overview for those working in related fields, and they identified several avenues through which blocking can be reduced in numerical models, although a fully reliable simulation remains elusive (at least, beyond a few days' lead time) [13]. Efe et al investigated the blocking characteristic related to surface temperature anomalies in Turkey between 1977 and 2016, and they found a negative correlation in all seasons during the study period except in spring, and observed Rex-blocking system for both maximum and minimum temperature anomalies [12].…”